package com.wqt;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;

/**
 * @ProjectName: ybxy6
 * @Titile: MapDemo
 * @Author: wqt
 * @Description: TODO
 */
public class MapDemo {
    public static void main(String[] args) {
        test3();
    }

    public static void test3(){
        Map<String, Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("李四", 200.0);
        map.put("王五", 300.0);
        map.put("赵六", 400.0);

//        map.forEach(new BiConsumer<String, Double>() {
//            @Override
//            public void accept(String key, Double value) {
//                System.out.println(key+"---"+value);
//            }
//        });

        map.forEach((key, value) -> System.out.println(key + "---" + value));
    }


    public static void test2(){
        Map<String, Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("李四", 200.0);
        map.put("王五", 300.0);
        map.put("赵六", 400.0);
        //1. 将map集合转成set集合（将map中的key-value绑定成一个对象entry）
        Set<Map.Entry<String, Double>> entrySet = map.entrySet();
        //2. 遍历set集合
        for (Map.Entry<String, Double> entry : entrySet) {
            //3. 根据entry获取key和value
            String key = entry.getKey();
            Double value = entry.getValue();
            System.out.println(key+"---"+value);
        }
    }


    public static void test1(){
        Map<String, Double> map = new HashMap<>();
        map.put("张三", 100.0);
        map.put("李四", 200.0);
        map.put("王五", 300.0);
        map.put("赵六", 400.0);
        //将map中的所有健值取出来放到set集合中
        Set<String> keySet = map.keySet();
        //遍历key集合
        for (String key : keySet) {
            //根据key去找值
            Double value = map.get(key);
            System.out.println(key+"---"+value);
        }

    }


    private static void test0() {
        Map<String, Double> map  = new HashMap<>();
        map.put("张三", 100.0);
        map.put("李四", 200.0);
        map.put("王五", 300.0);
        map.put("赵六", 400.0);
        map.put("赵六", 500.0);
        System.out.println(map);

        map.remove("张三");
        System.out.println(map);
//        map.clear();
//        System.out.println(map);

        boolean b1 = map.containsKey("李四");
        System.out.println("b1 = "+b1);
        boolean b2 = map.containsValue(200.0);
        System.out.println("b2 = "+b2);

        boolean empty = map.isEmpty();
        System.out.println("empty = "+empty);
        int size = map.size();
        System.out.println("size = "+size);
    }

}